1. Field of the Invention
The present invention relates to image-capturing devices, light adjustment mechanisms, and light control blades. In particular, the present invention relates to a light control blade that is integrally provided with a light adjustment filter so as to achieve lower manufacturing costs.
2. Description of the Related Art
A typical image-capturing device, such as a video camera and a still camera, is equipped with a light adjustment iris and a lens-shifting mechanism for shifting each lens in the optical-axis direction in order to perform focus control or zoom control. In a typical image-capturing device, the optical path of an optical image-capturing system is opened and closed by shifting a light control blade (i.e., a diaphragm blade) within a plane extending perpendicular to an optical axis of the optical system in order to adjust the amount of incident light. Specifically, the light control blade is included in the light adjustment iris and is shifted in response to a driving force of a driving motor.
In such an image-capturing device, if the amount of light from a photographic subject is too large, it may be necessary to control the amount of light entering an image-capturing unit, such as a CCD (charge coupled device). Generally, in addition to the iris mentioned above, the amount of incident light is also adjusted through a light adjustment filter, known as an ND (neutral density) filter.
In related art, a light control blade includes a light-blocking portion defining a main body of the blade, and a light adjustment filter attached to the main body of the blade by, for example, bonding such that the light adjustment filter covers a cutout portion provided in the main body. The cutout portion is used for the light adjustment. The light adjustment filter and the main body of the blade are shifted integrally so that a light adjustment function of the light control blade is achieved. An example of such a light control blade is disclosed in Japanese Unexamined Patent Application Publication No. 2001-356386.